docs: def __get_language_data(self, bundleId, languageId, fallback=False):
          """``GET /{serviceInstanceId}/v2/bundles/{bundleId}/{languageId}``
  
          Gets the resource strings (key/value pairs) for the language. If
          ``fallback`` is ``True``, source language value is used if translated
          value is not available.
          """
          url = self.__get_base_bundle_url() + '/' + bundleId + '/' + languageId
          params = {'fallback': 'true'} if fallback else None
          response = self.__perform_rest_call(requestURL=url, params=params)
  
          if not response:
              return None
  
          languageData = response.get(self.__RESPONSE_RESOURCE_STRINGS_KEY)
  
          return languageData